Experimental investigation of the compressive strength of hybrid composite sandwich beams with double-corrugated sinusoidal core reinforced by graphene and polyurethane foam

In this paper, the effects of some system parameters such as nanographene, core geometry, and polyurethane foam on the compressive strength of composite sandwich beams with double corrugated lattice core subjected to flatwise-compression load are investigated experimentally. The face sheets and core of the sandwich beams are made of 10-layers bidirectional carbon fibers using the vacuum infusion process. According to the results of the flatwise-compression test, it was revealed that some factors, including height and angle of the core, the weight percentage of nanographene, and polyurethane foam, can be considered as effective parameters to enhance the compressive strength of the composite sandwich beams. Scanning electron microscopy images were utilized to observe the composition and distribution of the nanoparticles. It was observed that adding nanographene particles to the composite laminates significantly affects the mechanical properties and flexural strength of the sandwich beams. In addition, experimental results showed that the shape of the core can be an effective parameter to control the elasticity and strength of the sandwich beams, and also polyurethane foam dramatically increases the compressive strength and can postpone core failure.